Untucked, loose shirt. Honestly, I think people worry too much about "printing." I've been carrying now for 4 years, since Ohio passed the CCW law, and I have never been "made." You don't need the gun to completely disappear, just cover the darn thing. A slight lump on your side will alert NO ONE. People will think it's a cellphone.
Just a few nights ago I wore my N-Frame 4" S&W, OWB with a Milt Sparks PMK. It's fairly hot here in Ohio and I just wore a t shirt over top. Guess what? No one noticed. This wouldn't be my preferred rig if I were going to a (non alcohol serving, of course) restaurant, as it would stick out below the shirt if I sat down. But walking around in a store? Forgetaboutit.
I'm not a big guy. 5'11" 155lbs.
People worry WAY too much about printing. I personally think a
comfortable holster is way more important than "extreme deep concealment" which is what everyone seems to go for. As in
your comfort. If you're comfortable, and not constantly fidgiting and thinking "damn, I have a GUN on!" then you'll be calm, cool, and collected... Just like everyone else. No one will notice a thing. Do you look at every lump on everyone's side and think "is that a cellphone or a GUN??" Dunno, not me. There are a lot of cellphones around here
Would a hawaiian print shirt be better? Sure. I didn't have one on, though, and a quick mirror check revealed little more than a "cellphone lump" so I knew I'd be fine.
Now, I don't necessarily recommend constant carry of a full size 1911 or N frame. They're heavy. Most of the time in the superheat of the summer I carry a smaller auto IWB (now the PM9, sooooo light) or sometimes pocket carry depending upon mood/dress. But you CAN do it.
I find OWB carry more comfy than IWB, and I'm considering an OWB rig for my PM9. LIke I said, I just don't think EDC is that necessary in my environment. I don't think you need something that rides ABOVE the belt... That's too high and the gun will flop around. But something higher than my PMK (which rides very low) will be better, so when you sit down the gun won't "pop" out underneath the shirt. Something your shirttails will cover with a little extra for insurance.